In Italy there are private and public beaches. Everyone is allowed to go for free either in the private or the public beaches, none can ask you for money if you want only walk through. The space in front of the sea (between the end of the sea and 3 (somewhere 5) meter from the ending of the sea) it is called "Battigia" and it is public everywhere. On the Battigia is not allowed for safety reason to leave any towel, bag pack, umbrella for sun, chairs, ecc... it has to remain totally free. On the Battigia you are only allowed to walk through and having a bath (for free everywhere). For sure you can even stop there, none can force you to leave if you want to stand there or sit with your friends (without leaving any personals belongings).
If you need instead to leave behind your personal belongings without paying it is more convenient to look for a free beach. Otherwise you can rent (in the private beach) an umbrella / sunbed (in Italy it is called "Sdraio" or "Lettino" and "Ombrellone").
Some people (especially on the private beaches ;-)) could be disappointed and try to chase you to buy a daily ticket, but with this rule in your mind you will have enough arguments to reply to them ;-)!!!